start.js

There is only word which is synonymous with Angular, C H A N G E. Few months ago I made a post on Angular2 & now we have landed on Angular5. It is definitely challenging to keep us on par with the latest in the Angular world.

So to keep my dice rolling, I decided to make my angular posts into a series. In this we look at debugging our unit tests on a browser. In Javascript world, we all know and/or have used Jasmine for Unit Testing at some point.

By default it runs on a headless browser (usually PhantomJS) so we launch the test case/suite from terminal & just wait till test results but we never get to see anything!

But if we change this to a browser like Chrome, we could actually see how the test cases are being executed. Just like UI automation tests, fro example, this would show us text being inserted on forms, button being clicked & etc. Without no more explaination, let’s dive into how we establish this; Just 3 steps!

05 | Barrel Files for the rescue

One of the first things you will notice when you start working on it is, you have to write so many import statements. Gets worst, when you have to make 2 dedicated imports to get hold of 2 components sitting inside the same folder.

Well, this isn’t one of those where you blame at Angular! This is something to do with Typescript. The resolution is to use barrel files. As a practice you can start creating an index.ts file in each of your folders containing services, components or feature modules.

06 | Running the App

07 | Unit Test and other CI/CD Concerns

There are scripts setup on package.json for these, one can refer it. For more on configuring karma & etc read this blog. Example, Running unit tests (jasmine – BDD):

ng test

08 | Need to create your feature module?

After sometime you realize your app module has grown out of proportion. It is time to consider some logical organization of your code. First is to consider organizing them into modules. Here is a neat read

09 | Adding a Simple Form

You will notice I’ve placed a simple form in ContactComponent. At this point it’s important that you don’t forget to import FormsModule in your app.module.ts.

However, one thing you will notice there is a realtime representation of form data. It is quite useful for you to debug, it can be achieved with the following peace of markup:

10 | Lifecycle Hooks

Intention behind post was to have an Angular2 guide which would help one to start a project from scratch & take it all way to deployment. I haven’t covered much of Angular2 concepts or structs on this post for brevity & aligning with my intention to keep it super short. However, Lifecycle Hooks are a thing it can’t afford to miss. Angular2 provides 8 of them in total: ngOnInit, ngOnChanges, ngDoCheck, ngAfterContentInit, ngAfterContentChecked, ngAfterViewInit, ngAfterViewChecked, ngOnDestroy. Here is an example:

11 | Before you go for Production

You are just a command away if you want to do a production build for your awesome app. Afterwards you just need to copy the generated dist folder to your live server.

ng build --aot --environment prod

Yet, there are few things one should know going to this step. When you execute above the step there are so many things happening behind the scene. Here are some, concatenation, minification, uglification & tree shaking.

Since I have already made a note on first 3 on a different blog, I would like you to come to terms with Tree Shaking.

Tree Shaking is the process of getting rid of dead code. If you’re coming from Java world or most other OOP environments, you will be familiar with a warning called ‘unused code/method’. However, if you want to go deep into it with examples & numbers here is great post from an expert. Minko Gechev is the author of the official Angular Style Guide.

If you are already an expert at Angular & came across this post whilst considering ways to improve the page load time & performance tuning for your app here is a great stack overflow thread which you shouldn’t miss!